GT6 fuel injection pump musings.

One of the complaints of the Lucas mechanical fuel injection system is the high pressure fuel pump. These pumps are directly driven via a electric motor sat on top of the pump. The main problem with this pump is it's habit of overheating and causing cavitation in the fuel pump. A common conversion is to replace the Lucas pump with a Bosch version.

In a search of another alternative, I have managed to get hold of a belt driven version of the Lucas fuel pump. These were supplied by Cosworth to work with the injection system used on BDG, DFV or YBB based engines.
With these pumps the engine is started using the old electric fuel pump, but once started, the electric pump is turned off and the belt driven pump takes over, delivering fuel at a rate proportional to the the engine revs and hence requirements. The system is designed such that excess fuel is always being fed to the metering unit and returned to the fuel tank, so it does not matter if too much fuel, up to a point, is sent to the metering unit.

For now this pump will be put aside until the GT6 is on the road, though I have started considering how to integrate it into the existing system. Once the car is running, fuel will have to bypass the electric pump to the belt pump, so this could be done by taking a second fuel line from the fuel tank to the belt pump or by having some sort of bypass for the electric pump with a one way valve.
Another alternative idea I had this afternoon was to replace the original electric pump with the new belt driven pump, driven from a different electric pump instead on the engine. The advantage of this setup would be that the electric motor is distanced from the pump, keeping the temperature down and it would cut out the need for extra fuel lines around the engine bay.